Did you disconnect the battery before the work? You may have to do the airbag reset but the code seems to indicate other issues. Try the reset first (
Flashing Airbag Light After HU Install)
B1065 NISSAN Possible Causes
Faulty Assist Air Bag Module
Assist Air Bag Module harness is open or shorted
Assist Air Bag Module circuit poor electrical connection
Faulty Diagnosis Sensor Unit